This was, I think, in the aviary opposite the Spider Monkeys, between the various monkey enclosures, and the Scripps Aviary. The other birds in that aviary are Weavers, Cordon Bleus, Whydahs - various African species. This one is stumping me. I think it's a female Purple Grenadier (Uraeginthus ianthinogaster) but I'm not certain. Any help gratefully received.....